Lei Ping, Li Yaohua, Chen Xin, Yang Shuyuan, Zhang Jianning
Department of Neurosurgery, Tianjin Neurological Institute, General Hospital, Tianjin Medical University, Lab. of T.J.I.V.R., 154 Anshan Road, Heping District, Tianjin 300052, PR China.
Brain Res. 2009 Aug 11;1284:191-201. doi: 10.1016/j.brainres.2009.05.074. Epub 2009 Jun 6.
MicroRNAs (miRNAs) are very important regulators of biological processes such as development, cellular differentiation, and tumor generation. MiRNA microarray has been found to be a high throughput global analysis tool for detecting miRNA expression profiling, and miRNA expression profiling will facilitate the study of the biological function of miRNAs. In this report, we describe the miRNA expression level in rat cerebral cortex after traumatic brain injury using microarray method. We choose several time points post brain injury: 6 h, 24 h, 48 h and 72 h, respectively, to reveal differential expression of miRNAs in rat brain cortex compared with control groups. Our research revealed that 136 miRNAs were expressing at 6 h post injury, in which 13 miRNAs were more than 2-fold up-regulated, and 14 miRNAs were more than 2-fold down-regulated; 118 miRNAs were expressing at 24 h post injury, in which 4 miRNAs were more than 2-fold up-regulated, and 23 miRNAs were more than 2-fold down-regulated; 149 miRNAs were expressing at 48 h post injury, in which 16 miRNAs were more than 2-fold up-regulated, and 11 miRNAs were more than 2-fold down-regulated; and 203 miRNAs were expressing at 72 h post injury, in which 19 miRNAs were more than 2-fold up-regulated, and 5 miRNAs were more than 2-fold down-regulated. Furthermore, we revealed global up-regulation of miR-21 expression within all the four time points post injury. Finally, we utilized qRT-PCR methods to verify the microarray results. The qRT-PCR results indicated good consistency with the results of the microarray method. Our microarray based analysis of microRNA expression in rat cerebral cortex after traumatic brain injury has shown that some microRNA such as miR-21 could be involved in the intricate process of TBI course.
微小RNA（miRNA）是生物过程（如发育、细胞分化和肿瘤发生）的重要调节因子。已发现miRNA微阵列是一种用于检测miRNA表达谱的高通量全局分析工具，而miRNA表达谱将有助于研究miRNA的生物学功能。在本报告中，我们使用微阵列方法描述了创伤性脑损伤后大鼠大脑皮层中的miRNA表达水平。我们选择脑损伤后的几个时间点：分别为6小时、24小时、48小时和72小时，以揭示与对照组相比大鼠脑皮层中miRNA的差异表达。我们的研究表明，损伤后6小时有136种miRNA表达，其中13种miRNA上调超过2倍，14种miRNA下调超过2倍；损伤后24小时有118种miRNA表达，其中4种miRNA上调超过2倍，23种miRNA下调超过2倍；损伤后48小时有149种miRNA表达，其中16种miRNA上调超过2倍，11种miRNA下调超过2倍；损伤后72小时有203种miRNA表达，其中19种miRNA上调超过2倍，5种miRNA下调超过2倍。此外，我们发现在损伤后的所有四个时间点内miR-21表达均全局上调。最后，我们利用qRT-PCR方法验证了微阵列结果。qRT-PCR结果与微阵列方法的结果显示出良好的一致性。我们基于微阵列对创伤性脑损伤后大鼠大脑皮层中微小RNA表达的分析表明，一些微小RNA如miR-21可能参与了创伤性脑损伤过程的复杂进程。
